Probably because old calendars (such as the Persian Calendar) used 360 days for a year-when they watched the stars they saw them revolve around the North Star one degree per day.
September 27, 2015 will bring a supermoon lunar eclipse at nightfall. The last lunar eclipse of this magnitude occurred in 1982, and the next one of a similar magnitude will be in 2033. A lesser lunar eclipse will come in 2018. The lunar eclipse part of this phenomenon, according CTV, is caused by the Earth inserting itself between the sun and the moon. As this happens, the Earth casts its shadow on the face of the moon.
The next Lunar Eclipse will be a Total Eclipse and occur on April 4th, 2015. It will be visible in Asia, Australia, Pacific and the Americas. This Lunar Eclipse Calendar is a listing of all Lunar Eclipses from 2015, 2016 and 2017. The cart shows the date of each eclipse as well as the duration and type of Eclipse. The Map shows the general location that the Eclipse will be visible in.